In the production of insulated panels or containers, for example, of the general type disclosed in U.S. Pat. Nos. 3,416,692, No. 5,082,335, No. 5,252,408 and No. 5,273,801, it is known to place a panel of microporous insulation material, such as a rigid foam having extremely small open cells, within an envelope or bag of an air impervious flexible barrier film. A plurality of the open bags are then usually placed within a vacuum chamber which evacuates air from the foam, after which each bag is sealed while in the vacuum chamber. It is also known to evacuate a sealed insulation bag by attaching an evacuation tube to a sealed bag, for example, as disclosed in above-mentioned Pat. No. 5,252,408.
In the production of vacuum insulation panels such as disclosed in the above-mentioned patents, it is desirable to provide for rapid evacuation of the air from the microporous insulation media, especially from foam material within large panels, and to assure that substantially all of the air is evacuated from the media. It is also desirable to determine that an evacuated panel does not have any leakage before the panel is sealed and to provide for efficiently producing a vacuum insulated box-like container which has minimal panel joints in order to minimize thermal leak paths and provide the container with a maximum R value.